# What are the oxidation numbers for carbon in carbon monoxide, and in methanol?

Jun 1, 2017

We have $: \stackrel{I {I}^{+}}{C} \equiv O$ versus ${H}_{3} \stackrel{I {I}^{-}}{C} O H$, so methanol has the carbon with the lower oxidation state.

#### Explanation:

The sum of the oxidation numbers equals the charge on the molecule, and both molecules are neutral.

Here are some rules that don't need to be remembered, but do have to be implicitly used.

$1.$ $\text{The oxidation number of a free element is always 0.}$

$2.$ $\text{The oxidation number of a mono-atomic ion is equal}$ $\text{to the charge of the ion.}$

$3.$ $\text{For a given bond, X-Y, the bond is split to give } {X}^{+}$ $\text{and}$ ${Y}^{-}$, $\text{where Y is more electronegative than X.}$

$4.$ $\text{The oxidation number of H is +1, but it is -1 in when}$ $\text{combined with less electronegative elements.}$

$5.$ $\text{The oxidation number of O in its}$ compounds $\text{is usually -2, but it is -1 in peroxides.}$

$6.$ $\text{The oxidation number of a Group 1 element in a}$ $\text{compound is +1.}$

$7.$ $\text{The oxidation number of a Group 2 element in a}$ $\text{compound is +2.}$

$8.$ $\text{The oxidation number of a Group 17 element in a binary}$ $\text{compound is -1.}$

$\text{9.}$ $\text{The SUM of the oxidation numbers of all of the}$ $\text{atoms in a neutral compound is ZERO.}$

$10.$ $\text{The SUM of the oxidation numbers in a polyatomic ion}$ $\text{is equal to the charge of the ion.}$

Jun 1, 2017

wkt oxd no of O= -2
oxd no of H=+1

#### Explanation:

Now let the oxd no of C ( the central atom )= x
1) CO
so,no net charge then
x+ (-2) =0
x= +2
2) CH3OH
so,no net charge then
x+ 3*(+1) + (-2) + 1 = 0
x + 2 = 0
x= -2
Hence , from CO and CH3OH , C has least oxd state in CH3OH .

.........................................HOPE IT HELPS.........................:)